Heat-interchanging apparatus.



L. D. LOVEKIN.

HEAT lNTERcHANGTNG APPARATUS.

` APPLICATION FILED )UNE 5.1916. 1,235,908..

Patented Aug. 7

2 S H E E T S- SHEET T.

I. n. LovEKINf HEAT INTERCHANGING APPARATUS-I APPLIC'ATION FILED IIINE 5,1916.

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LUTHER D. LOVEKIN, OF PHILADELPHIA, PENNSYLVANIA.

HEAT-INTERCHANGING APPARATUS.

4 Specification of Letters Patent.

Patented Aug. 7, 1917.

Application led June 5, 1916. Serial No. 101,673.

To all 'whom z't may concern.' v

Be it known that I, LUTHER D. LovEKIN, a citizen of the United States of America, and resident of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a certain new and useful Improvement in Heat-Interchanging Apparatus, of which the following is a true and exact description, reference being` had to the accompanying drawings, which form apart thereof.

My presentinvention relates to heat interchanging apparatus of the well known type in which the exchange of heat between two fluids is eEected by causing one to iow through a group of tubes traversing a space into which the other fluid is passed.

The object of my invention is to provide apparatus of the type referred to, characterized on the one hand by its eciency and relatively large capacity per unit of bulk, and on the other hand by its inherent simplicity, durability and relative low cost of manufacture.

Thev various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, and the advantages possessed by it, reference should be had to t e accompanying drawings and descriptive matter in which I have illustrated and described the preferred embodiments of my invention.

Of the drawings:

Figure l is a sectional elevation of heat interchanging apparatus embodying a preferred form of my invention, the section being taken alongthe broken line 1-1 of Fig. 2 is an elevation, viewed from the inner side, of one of the chambered end members;

Fig. 3 is an elevation, viewed from the inner side', of the other chambered end member' Fig. 4 is a partial sectional elevation of one of the tubes yof the retarding element with a portion of the retarding element mounted therein;

Fig. 5 is an elevation of one of the tube sheets employed;

.modified form of my invention.

The apparatus illustrated in Figs. 1 to 7 inclusive was primarily devised for use on a locomotive to preheat the feed water supplied to the locomotive by the use of exhaust steam from the latter. It is to be understood, however, that the apparatus in the particular form shown, is adapted for many other uses, and that my invention is generally applicable to heat inter-'changing apparatus of the general type referred to above.

In the particular apparatus shown in Figs. l to 7, a plurality of parallel closely spaced tubes A, are expanded or otherwise rigidly secured at their ends to similar tube sheets B and BA. Secured to the remote or outer sides of the tube sheets B and BA, are chambered end members C and D respectively. Advantageously in some, though not in all cases the apparatus is formed as shown, with circular tube sheets and end members, and with the tubes arranged in a cylindrical mass. The chambered end member C is formed with a rib or circular portion C engaging the tube sheet B in a circular Zone closely surrounding the tubes A. The end member D is similarly formed with a rib or portionA D engaging the tube sheet BA. Advantageously in many cases the tube sheets may each be grooved as'indicated at B', to receive-a gasket F against which the corresponding end member portion C or D directly engages. Each of the end members C and D is secured to the corresponding tube sheet by a 'series of stud bolts E screwed into threaded apertures formed in the tube sheet and extending in a circular series closely surrounding the groove B. The end member C is formed with internal webs C7 engaging the tube sheet B at their free edges and dividing the space between the latter and the outer wall of the end member proper into an inlet compartment C2, an outlet comartment C4, and a compartment C". The inlet and outlet compartments are` of the same size and each half as large as the compartment C3 which is separated from the chambers Cg and C* by a diametral line. The end member D is provided with a single rib or web engaging the corresponding tube sheet along a diametral line in the same plane as the partition or web separating the chambers C` and C4 of the end member C.

One of the fluids to be thermally acted upon, as for instance, feed water to be preheated, is admitted to the inlet compartment C2 through the inlet opening C5, thence it passes through the group of tubes A communicating with the space C2 to the chamber D2 in the end member D. From there it returns to the chamber C3 of the end member C through the tubes A connecting the latter chamber with the chamber D2. From the chamber C8 the water again passes to the opposite end of the apparatus through the' tubes connecting the chamber C3 to the chamber D3, and from the chamber D3 the water passes to the outlet chamber C4 through the tubes A connecting the latter chamber to the chamber D". The heated water passes out of the chamber C4 through the outlet port C".

To prevent the passage of the water in unbroken stream lines through the tubes A and hence to increase the heat transfer capacity of the tubes, I preferably extend through each tube, a retarding element Gr preferably formed by twisting a transversely corrugated metallic ribbon into a helix. To prevent axial displacement of the retarding elements, I form apertures through the projecting ends of the latter and thread or lace a wire through the apertures in the retarding elements G at the outer side of each tube sheet. p v

Surrounding the tubes A is a casing element I which in the preferred construction illustrated in Figs. 1 to 7, comprises a cylindrical body of wrought metal with outturned ange portions I at each end which may be of the same material as the body of the casing, and in practice are preferably formed separate from the latter and then welded thereto. Each flange portion I comprises an outer portion abutting against the adjacent side of the corresponding tube sheet in a zone surrounding the bolts E and rigidly and permanently secured to the tube sheet as by the rivets J. As shown, the construction is strengthened by clamping the outer portion of the flange I between the corresponding tube sheet and a washer llke member K through which the rivets extend. Each end por-tion I is advantageously curved generally as shown, for the double of the tubes and the casing I, and to provide aclearance space between the ends of the bolts E and the flange portions I in line therewith. The provision of this clearance insures against any disturbance of the connection between the casing I and thel corresponding tube sheet in case a bolt E is caused to project through the tube sheet in the initial assembly of the apparatus or in any subsequent inspection or repair operation to which it may be subjected.

. L represents a cast metal inlet casing secured to the body of the casing I communicating with the space inclosed by the-latter through a port or ports formed in the casing body. Advantageously, the communication between the chamber in they inlet casing L and the interior of the casing I is through a series of relatively small ports I2 formed in the casing body which serve to break up into small streams, the exhaust steam or other fluid admitted to the interior of the casing I. Similarly, an outlet casin M is secured tothe under side of the casing I and the water of condensation or other. fluid discharged from the interior of the casing I passes out of the latter through the port I3 into the outlet casing M and thence escapes from the apparatus ordinarily through piping secured to the casing M and communicating with the outlet port M formed in the latter.

The apparatus disclosed in Figs. 1 to 7 is wel-l adapted to attain the object of my invention as set forth above. The provision made for passing the water or other iuid flowing through the tubes A in series through a plurality of groups of these tubes provides a relatively long tube path andhence makes possible the relatively high velocity of flow through the tubes which is essential to secure commercially high rates of heat transfer. The rate of heat transfer is very substantially augmented also by the-provision of the specialretarding element G,`and it is to be noted that with the construction described, in case of the destruction of some or all of these retarding elements from the erosive action of the water or other fluid passing through the tubes, especially when impure, it is possible to quickly renew the retarding elements or, if extra retarding elemay be quickly and easily renewed and the apparatus thus left in operative form, though, with a reduced effectiveness. The desired relatively high efficiency and large capacity per unit of bulk thus secured is obtained, moreover, with a construction with is inherently simple, durable and relatively inexpensive to manufacture. The casyments are not available, the broken parts permanent one, the effectiveness of which is in no wise impaired by such flexing of the inner portions of the flanges I as are necessary to accommodate thermal expansion and contraction of the parts. The fact that these connections are permanent and are not disturbed when the chambered end members are removed from time to time is of much practical importance. This avoids the diiculty of providing a satisfactory form of detachable connection between the flexible flanges I and the end members, and avoids the impairment of the anges practically certain to result from repeatedly connecting them to and disconnecting them from the chambered end members, and of course avoids unnecessary labor and expense in effecting such connections and disconnections.

While I prefer in many cases to form the body of the casing I of the same material as, and to integrally connect it to the flexible flange portions I, I may also form the body of the casing of cast metal. In this case I connect the latter at one end at least, to the corresponding tube sheet by a separate flexible flange portion generally like the flange portion I of the construction shown in Figs. 1 to 7 Thus, in Fig. 8, I have illustrated an apparatus differing from that shown in Figs. 1 to 7 in that the casing body IA replacing the casing I of the construction first described, is formed at onel end with a rigid flange portion I10 secured to the adjacent tube sheet as by means of the bolts E employed to secure the corresponding end member D thereto. The body of the casing member IAl terminates at its other end a slight distance short of the tube sheet to which the end member C is connected. A flexible liange member IB which in its outer portion may be shaped like the flanges I may be and is shown as being connected to thel tube sheet B exactly as 1s the flange portion I of the construction first described. The flange portion IB comprises .acylindrical portion fitting about the adjacent end of the casing IA and secured to the latter by rivets or screws O.

While in accordance with the provisions of the statutes I have `illustrated and described the best forms of my invention now known to me, it will be apparent to those skilled in the art that certain changes can be made in the form of my invention without departing from its spirit, and that some features of my invention can be used without a, `corresponding use of other features.

Havingnow described my invention, what I claim as new and desire to secure by Letters Patent, is

1. Apparatus of the type described comprising in combination a plurality of tubes, a pair of tube sheets to'which the opposite ends of the tubes are rigidly connected, a chambered end member secured to one of said tube sheets by a series .of bolts extending around the portion of the tube sheet to which the tubes are connected and a casing surroundin the tubes and comprising an outturned exible flange portion at one end` which abuts against the last mentioned tubel sheet and is secured thereto along a zone v l surrounding the bolts connecting said chambered end member and tub'e sheet.

2. Apparatus of the type described comprising in combination a plurality of tubes, a pair of tube sheets to which the opposite ends of the tubes are rigidly connected, a chambered end member secured 4to one of said tube sheets by a series of bolts extending around the portion of the tube sheet to which the tubes are connected and a casing surrounding the tubes and comprising an outturned flexible flange portion at one end which abuts against the last mentioned tube sheet and is secured thereto alon a zone surrounding the bolts connecting sa1d chambered end member and tube sheet and is separated by a clearance space from the zone o the tube sheet into which said bolts are secured.

3. Apparatus of the type described com- Y prising in combination a plurality of tubes, a pair of tube sheets to which the opposite ends of the tubes are rigidly connected, chambered end members secured one to each of said tube sheets by a series of bolts extending around the portion of the tube sheet to which the tubes are connected, and a casing surroundin the tubes and comprising an outturned exible flange portion at its ends each of which abuts against the corresponding tube sheet and is riveted thereto along a zone surroundinglthe bolts connecting the corresponding chambered end member to said tube sheet, and is separated by a clearance spacefrom the zone of the corresponding tube sheet into which said bolts are secured. v

4. Apparatus of the type described comprising in combination a plurality of tubes, rctarding elements mounted in said tubes, tube sheets to which the opposite ends of the tubes are rigidly connected, chambered end members connected to the tube sheets each by a series of bolts surrounding the portion of the tube sheet to which the tubes are connected, said end members being formed with inlet and outlet ports and partitions arranged in conjunction with the tubes to provi e a How path comprising a lurality of passes between the two end mem ers, and Vai casing surrounding the tubes and compris- 5 ing an outturned exible flange portion at its ends each of which vaatbuts a einst the corresponding tube sheet and is riveted thereto memos along a, zone surrounding the bolts connecting the corresponding chambered end member to said tube sheet, and is separated by a. 10 clearance space from the zone of the corresponding tube sheet into which said bolts are secured.

LUTHER D. LOVEKIN. 

